int main()
{
    char str[] = "hello world\n";

    asm(
            "movl $4, %%eax; \n\t"
            "movl $1, %%ebx; \n\t"
            "movl %0, %%ecx; \n\t"
            "movl $12, %%edx; \n\t"
            "int $0x80"
            :
            : "r"(str)
            : "%eax", "%ebx","%ecx","%edx"
        );

    return 0;
}

